After prototyping Design Concept 8 of the Prop Control Bracket, I think I finally have a workable plan.
I converted the 3D model to GCodes to drive the CNC mill. First try in the shop was trouble prone. Somehow I had changed the machine configuration from mm to inches. When I ran the script, it created a part at 1/25.4 scale. Good for toys, but not for actual size.
After an hour or so, I found the setting to change and milling was uneventful.